Esterified epoxy polyesters



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United States Patent 2,907,735 ESTERIFIED EPOXY POLYESTERS S ylvan 0.Greenlee, Racine, Wis., assignor to S. C. Johnson & Son, Inc., Racine,Wis.

No Drawing. Application June 30, 1955 Serial No. 519,275

Claims. c1. 260-22 This invention relates to new epoxy polyesteradducts.

More particularly, this invention is concerned with novel ofplasticizing and imparting air-drying or heat conversion characteristicsWhile retaining other desired proper- According to conventionalpractice, the resin is compounded with one or more materials whichcontribute the plasticizing and/ or drying characteristics. Since theresin and plasticizer or drying oil must be completely miscible with oneanother, certain other properties of the resin are sacrificed. Forexample, a formulator will choose a very soluble resin because of itsmiscibility even though the product. is inferior with respect totoughness, chemical resistance or flexibility.

Long-chain unsaturated acids containing at least about 10 carbon atomsconstitute suitable plasticizers: These materials also are desirablebecause of the conversion characteristics imparted due to theirunsaturation. The

present invention provides a means of not only chemically combining suchacids witha particular resin, but because ofthe form in which the acidsare used, facilitates the preparation of materials containing a veryhigh proportion of the desired plasticizing or drying residues.

The reaction products which constitute the essence of this invention areprepared by partially or completely esterifying an epoxidized polyesterof tetrahydrophthalic acid and a glycol with an unsaturated diesteracid. By partial esterification it is meant that only 1 mol of thediester acid is employed .per epoxide equivalent weight.

of the epoxy polyester. that oneequivalent of the acid reacts with 1equivalent of the epoxide, the esterification involves direct splittingof the epoxide group by addition, resulting in one unre- By using theseproportions so acted hydroxyl group for each ester group formed. Thisreaction may be illustrated as followsi it Room -on Since this type ofreaction involves reaction of the temperature and timerequired foresterification of alcoholic hydroxyl groups. This isof particularadvantage in cases where it is desired to carry outthe esterificationduring a normal film curing baking process. For example, it isconvenient to formulate a heat-converting varnish by dissolving amixture of the diester acids with the epoxidizedpolyester resins in anorganic solvent, applying thin films of this mixture, and submitting thefilms to a normalfilin-converting treatment, such as '1 hourat 175 C.Heat treatment with this type of formulation iss'ufficient to bringaboutthe csterificationof the diester acids with the epoxide groupsthrough'dire'ct addition reactions (4-hydroxyphenyl)-pentanoic acid.

phenol and related groupof the keto-acid must be located next to aterminal carbon atom in order to obtain satisfactory yields. Prior asillustrated by the above reaction, and at the same time, cause olefinpolymcrizatiorithroug h the double bonds present in the unsaturatedportions of the diester acids. It is often desirable to add siiiallamounts of varnish driers, such as "a, cobalt drier,-to this mixture ofdiester acids and epoxy "resins before the heat treatment in order tocatalyze the olefin polymerization.

Forother applications, it maybe desirable to useniore completelyesterified products in which "case the diestr acidsare usedinquantitiesapproaching that equivalent to the available'esterifiable epoxide andhydroxyl groups of the epoxidized polyester resin. In this case thequantity of diester acid used would approach 2 mols of the diesteraeidper epoxide equivalent weight since the hydroxyl group liberated bythe epoxide addition reaction is esterifiable with a mol of the diesteracid. This reaction may be illustrated generally by the following.-

The materials contemplated for use in preparing the subject esterifiedepoxy polyester resins are those described and claimed in the copendingGreenlee application of even date Serial No. 519,274 entitledUnsaturated Diester Acids. These compounds are the esters of one or morelong-chain unsaturated acids and a bis- (hydroxyaryl)-substitutedaliphatic acid. Such compositionsma y be prepared, for example, byreacting 2 mols of the acid chloride of linoleic acid with 1 mol of4,4-bis- 1 The aryloxy-substituted acid contemplated for use inpreparing the desired unsaturated diester acid should have twohydroxyphenyl groups attached to a single carbon the desired phenol.Experience in the preparation of biscomp'ounds indicates that thecarbonyl applications, Serial Nos. 464,607 and 489,300, filed October25, 1954, and February 18, 1955, respectively, disclose a number ofillustrative compounds suitable for. use as the aryloxy-s'ubstitutedacid and methods of preparing the same. These materials, which arereferred to for convenience as Diphenolic'Acid, or DPA, consist of thecondensation products of levulinic acid and phenol, substitutedphenols,or mixtures thereof. It is to beunderstood 'thatthe' phenolic nuclei ofthe Diphenolic Acid may be substituted with any 'g'roupswhichwill notinterfere with they esterification' reactionsfFor example, the nucleimay be .alkylat'edwith alkylfgroupshaving up to '5 carbon atoms asdisclosed fin se'riai No. 489,300 or they may be halogenated.

The long-chain acids which are'contemplated for use in preparing thesynthetic e'sltersof this invention include.theunsatura't'ed,mono-carboxylicflacids of at least about .10carbonatoms'fand mixtures' thereof. Illustrative of such acids arethedrying'oil ,fattyacidS which normally contain from 18 .to 22 carbonatoms", such as acidsobtained by the s'aponifica'tioln ofnaturally-ioccurring un- EXAMPLE III The procedure followed in Example Iwas repeated except that'ai'like amount of thedehydratedcastor oil acidswas substituted for the soya fatty acids for conversion of the acidchlorides. These 2 chlorides were purified by r vacuum distillation .as.inExample I.

saturated vegetable oils including China-wood oil, oiticica w oil,linseed oil, soyabean' oil, corn oil, and cottonseed oil. The fish oilsconstitute another important source of operable'unsaturated acids. Thesematerials, derived principally from themenhaden and the sardine, containthe glycerides of highly unsaturated acids Jiand -havean: iodine valuerangingfromabout 130 to 190. Suitable acids may I I be produced layothersynthetic means, for example, mixed linoleic acids may be obtained by:saponifying dehydrated .castor oil. 0leic acid may be used ;to preparea linoleic .acidby hydroxylatingthe sameto form dihydroxystearic I 5acid, followed by dehydration of thelatter. Lower molecular weightunsaturated acids may also be used if only air-drying characteristicsare'desired, but those containing less than about 10 carbon atomscontribute little plasticization, An example of one ofthe lowerplasticizing acids contemplated is .undecenoic acid, a commerciallyavailable material, a decomposition product of castor oil acids.

The diester acids are conveniently prepared by the reaction ofDiphenolic Acid with the long-chain unsaturated acid chlorides using theacid chlorides in an amount equivalent ot the phenolic hydroxyl contentof the Diphenolic Acid. It is possible to add the acidchlorides.directlyto the 'Diphenolic Acid and obtain esterification without ap-DPAitself. "The 'esterification reaction is normally carried out in thetemperature range of 50150 .'C. ;It is usually desirable to facilitatethe removal of HCLas it is formed during the reaction by bubbling inertgas .through ,preciable interference by thecarboxylicacid group of thethe reaction mixture and/or by reducing the pressure considerably belowatmospheric pressure.

The following -.e.xarnples illustratethe method of preparing thecompounds of this invention. These embodiments are not intended to limitthe inventiomand should not be so construed. Quantities of materialsexpressed refer to parts by weight unless otherwiseiindicated.

Examples 1 to III illustrate the preparation of longchain unsaturatedacid chlorides .of ther'ty peusedin esterification o f the phenolichydroxyl groups of Diphenolic Acid.

EXAMPLE I The reaction was carried out in a 2-liter, J-S-neck flaskprovided with a dropping funnel, agitator, reflux condenser, "and athermometer; To an agitated mixture of .-P t 9f s va att aQ an J-ZQWParof ben ne s added hrou t e rqppia fu n o erap i de 2 hours 286 parts of.th ionyl chloride,;holding the temr ra e d i sr t iin h range el -60.65" C. The

temperature was maintained .at 6 5-%80 ?-.-Q. for an additionalIZF/zhours, followed by remo-yal g f the:be 7' and excess ,thionyl chloridennder'-re duced pressure.

After I QY -I'Qf h h a c a d u reactcd-sthiony ride, thecorresponding.acidachloride wasfinally purified by vacuum distillationat 3 pressure. I

, EXAMPLE -11 V v 'In a procedure identicalto that .usedin Example I,lin- Examples IV .to V1 inclusive illustrate the preparation ofunsaturated diester acids.

EXAMPLE IV -"I he preparation was carried out in a 3-neck flask providedwith a mechanical agitator, a thermometer, and a condenser attached toanexhaust system.-- A mixture of 71.5 parts of 4,4 bis(4-hydroxyphenyl)-pentanoic acid and 136 partsof the acid chloride of soya bean oil acid"from'Example -I was heated with'agitation a 70-85 C.

fora periodof 3 hours, after which the ternperature'was graduallyincreased to 136 C. over aperiod of 2:hours and maintained at thistemperature for an additional 2 hours. *Duringthe latter 4 hours of thereaction period this systemwas evacuated to a pressureof around 3040 mm.by using a water aspirator,-to facilitate removal of the-HCL The viscousliquid .product had-an acid value of '89, a hydroxyl value of 21, andasaponification value of 225. Saponification value as used hereinisdefined as the number-of milligrams of KOH which are required tosaponify the ester present in a one-gram sample. The hydroxyl value asused'herein isthe number of milligrams of KOH equivalent to the-hydroxylcontent in a one-gram sampleof materials. 7

EXAMPLE V parts of the viscous diester of linseed oilacid chlorides fromExample II and 37 /2 parts of 4,4-bis(4-hydroxyphenyl)-pentanoic acid,were reacted according to the procedure of Example IV. The product 'hadan acid value of '84, a saponification value of 222, and a hydroxyl{value of 8.

EXAMPLE VI A viscous diester acid .prepared inthe manner .de-

scribed-in Example IV from 75 parts of thedehydrated .castor oil acidchlorides of Example III and 37 /2 parts .of'4g4-zbis(4rhydroxyphenyl)-pentanoic acid had an acid .value of;86,a-saponification value of2l8, anda hydroxyl value-of '12.

I The .epoxidized polyester resins suitable for use vinpre- :paring.-the subject .adducts are .described in detail in the copendingGreenlee application .SerialNo. 503,323, filed April 22, 1955. They arepolymeric materials prepared by esterifying tetrahydrophthalic anhydridewith a glycol, and containing up to about 15 monomeric-units permolecule. Any one of a number of difierent epoxidized poly- -.esterresins Tare suitable for use herein, variations being -dependent uponthe-extent of esterification and the glycol .ernployed.

--Compl ete esterification of. the available epoxide and .hydroxylcontent of the epoxidizedqpolyester resins may .be effected by .heatinga mixture of 2 mob of the diester ,penepoxide equivalent weight of theformer at l27 5' .C -The reaction is carried out under'conditions suchthat .w'ateris removed as it is formed by the esterification reaction.The removal of the water vapor is facilitated by bubbling :inert gasthrough the reaction mixture or by re- ..moving the water by 'azeotropicdistillation with a small amount .of hydrocarbon solvents, such asmineral spirits :or xylene.

; Partial esterification of the epoxidized polyester resins beaccomplished by employing an amount of unsatuweaves the former, attemperatures ofl00200 CV Since this esterification reaction takesplace'at relatively low temperatures and in relatively shortfperiods oftime, it may be effected simultaneously with the-conversionof themixture, through its unsaturated portions, to theinfusible, insolublestate. For example, aformulation to be used in a coating compositionmight be made up of a mixture of l mol of the diester acid and lepoxideequivalent weight of an epoxidized polyester resin, both dissolved inan, .organic solvent. By applying the composition inthin films andbaking for minutes to 2 hours, depending on. the temperature, theesterificationand conversion maybe carried out in situ. I

The following example illustrates the preparation of'a typicalepoxidized polyester resin of tetrahydrophthalic anhydride and1,4-butanediol. i

EXAMPLE 1; 4 A. Preparation of polyester from te'trahydroph tha lictinhydr ide and l 4-butqltediol mixture was then filteredrfollowedbypressin'g' as much of the solution as possible from theanion exchangeresin In a 3-neck flask provided with aitl ermometer, a

mechanical agitator, and, reflux condenser attached through a water trapwas placeda' mixtureof 1.1 mols tetrahydrophthalic .anhydride and 0.2mol n-butanol. After melting the tetrahydrophthalic anhydride .in thepresence of the butanol, 1 mol of 1,4-butanediol was added. The reactionmixture was gradually heated with agitation to 225 C. at 'which point asuflicientamount of xylene was added to give refluxing at theesterification temperature. The reaction mixture was then heated withcontinuous agitation at 225-235 C. until the acid value decreased to8.6. Acid value as herein described represents the number of milligramsof KOH equivalent to the acidity present in a one-gram sample. Theproduct was a highly viscous, tacky solid having slight flow at roomtemperature.

B. Epoxidatz'on 0f the polyester resin of Part A In a 3-neck flaskprovided with a thermometer, a mechanical agitator, and a refluxcondenser was placed 107 parts of the dehydrated acid form of a cationexchange resin (Dowex 50X-8, 50-100 mesh, Dow Chemical Company) and 30parts glacial acetic acid. vThe mixture of cation exchange resin andacetic acid was allowed to stand until the resin had completely taken upthe acid. To this mixture was added 273 parts of the polyester resin ofPart A dissolved in an equal weight of xylene. To the continuouslyagitated reaction mixture was added dropwise over a period of 45 minutesto 1 hour 75 parts of 50% hydrogen peroxide. The reaction temperaturewas held at 60 C. requiring the application of some external heat. (Insome preparations involving other polyester resins, suflicientexothermic heat is produced during the addition of hydrogen peroxide sothat no external heat is required, or even some external cooling may berequired.) The reaction was continued at 60 C. until a milliliter sampleof the reaction mixture analyzed less than 1 milliliter of 0.1 N sodiumthiosulfate in an iodornetric determination of hydrogen peroxide. Theproduct was then filtered, finally pressing the cation exchange resinfilter cake. The acid value of the total resin solution was 56.9. Thepercent nonvolatile of this solution amounting to 559 parts was 50. (Theepoxide values as discussed herein were determined by refluxing for 30minutes a 2-gram sample with 50 milliliters of pyridine hydrochloride inexcess pyridine. [The pyridine hydrochloride solution was prepared byadding 20 milliliters of concentrated HCl to a liter of pyridine] Aftercooling to room temperature, the sample is then backtitrated withstandard alcoholic sodium hydroxide.)

. The 559 parts of resin solution was thoroughly mixed with 175 parts ofthe dehydrated basic form ot-Dowex 1 (an amine type anion exchangeresin). The resulting .of 60 minutes at 175 cake. This product had anacidvalue of 10.1 on the nonvolatile resin content. Theepoxideequivalent was 304 onthe nonvolatile resin content. The nonvolatilecontent was 45%. N Examples VIII to Xillnstratethe formulation ofmixtures of. the'diestenacids' with the epoxidized polyesterresinslimiting the amount of :acid to that equivalent to the epoxideCOIllIBIltrOf the resin and their conversion to insoluble,' infusibleproducts.

. AMP 3V1I1 To a mixture of 2 0 'parts of a-45% solution of the diesteracid of ExampleIV-in xylene mixed with l0 parts of the product ofExample VII was add.ed cobalt naphthenate-paint drier in a quantityamounting to .03% of the nonvolatile content of the diester acid. Thinfilms of this-varnish flowed on to tin panels and heat treated in anoven for 60 minutes at 175 C. gave conversion to a tack-freesurface'which was unaffected by exposure to boiling water for 9 hours,or by exposure to 5% aqueous NaOH for a period of 3 hours. Hard, tough,flexible films were also obtained by using a curing schedule of 10minutes at 200 C. p

EXAMPLE IX The procedure followed in Example VIII was repeated exceptthat the soyabean oil diester acid of Example IV was replaced by 20parts of a 45% xylene solution of the linseed oil diester acid. of.Example V. This mixture resulted :in films which onheattreatment for aperiod C. were unaffected after 9 hours in boiling water or by exposure.to 5% aqueous NaOH for a period of 10% hours. Tack-free surfaces wereobtained on curing this composition for 15 minutes at C.

EXAMPLE X The procedure of Example VIII was repeated, using 20 parts ofa 45% xylene solution of the dehydrated castor oil diester acid ofExample VI. The resulting films, after heat treatment for 1 hour at C.,were unafiected after 9 hours in boiling water 5% aqueous NaOH for 3hours. version 'is obtained on heat treatment for 15 minutes at 150 C.

Examples XI and XII illustrate the preparation of varnishes by firstesterifying the diester acids with the epoxidized polyester resins.

EXAMPLE XI After removal of the volatile solvent from the epoxidizedpolyester resin of Example VII a mixture of 1 part of the epoxidizedpolyester resin and 2 parts of the diester acid of Example IV weregradually heated to a temperature of 200 C. with constant agitation andheld at this temperature for 1 hour. The product was then dissolved inxylene to a nonvolatile content of 50% and treated with .015 cobaltnaphthenate drier based on nonvolatile content. Thin films of thisproduct flowed on to tin panels and heat treated for a period of 30minutes at 175 C. gave hard, tough, flexible films.

EXAMPLE XII After removing the volatile solvent from the product ofExample VII, a mixture of 1 part of this epoxidized polyester resin and3 parts of the product of Example V were heated with continuousagitation to a temperature of 200 C. and held at 200-225 C. for a periodof 5 hours after which the product was dissolved in xylene to give anonvolatile content of 50% and treated with .015 cobalt naphthenatedrier (based on the non volatile content). varnish was obtained whichwhen spread in thin films gave tack-free surfaces after airor exposureto Tack-free film con- 7 drying rovernight or after heat treatment for aperiod oflimintttes at- 175C. 1 l a I it is to he iinderstood thatntheabove examples are intended to bo-illustrative only. They should not beconstrued as limiting therscope of (the present invention sinceembodiments other than those specifically disclosed may be producedwithout-departingfron'i invention concept (taught. I tis-desired;therefore, that" only such limitationsr b'e imposed ontheaappendedclaims asare stated therein or required byxithe prior art.

What is claimed is: r

1. A new composition of qmatter -comprising the ester of (A) anepoxidized polyester or tetrahydrophthalic acid and -a glycol-; saidpolyesterfliaving an average of more than one epoxygro up where'ih thepoieyoiryge n atom is linked to adjacent "carh'on atonis inthenuc-le'u's of said acid with {(B2) the -diester or (a) at lea-st oneethylenieally unsaturated aliphatic monocar boxylic acid having at leastabout carbon}.atom s and free of alcoholic hy droxyl groups with (b)ap'entanoic -'-'a'c'id cO'nsistingesSentially of'4'; 4bis(4-"hydroxyaryl) p'ent'arloic acid wherein the hydroxyaryl radicalis"alhydroxyphenyl radical and is free fromiisubstituents other'thanallcylgroups of from 1-5 carbon atoms,- theIester linkages-of -saidester of (A) with (B) being developed at least partially by the additionof the carboxyl groupwof diester (B) with the epoxy groups of thepolyepoXy polyester(A) r 2.- A new compositioneomprising' a condensationproduct of (A) -an epoxidized =polyester 0f tetrahydrophthalic acid anda glycol, said polyester having an average of more than one epoxy groupwherein the epoxy oxygen atom is linked'to adjacent carbon atoms in thenucleus of said acid and .(B) .the diester of (a) at least \one ;eth-;ylenically" unsatnr'atedtlaliphatie monooarboxylieaeid'hav:ingvat'lea'st abeut" 10 carbon atoms rand-tree 1of ia-lcoholie hydroxylgroups with (b) a pentanoic-ac'id consisting essentiallyvofAAibis(AmydrOKYa YD eIitanoie aeidwhem in the hydroxyaryl radicalis a,hydroxyphenyiiradiealzand is itreeifrom substituents other than alkylgroups of flora 1+5;earbonatorns;

3;:"Ihe composition .of claim-2 where pentanoio 8. The composition ofclaim 4 wherein said-acid a) i is linseed oilacidst a t p v r. i i F9.The compo "tion ofclaim 4 wherein said -aoid -(a isdehydrated' castoroilacids. s .v "1'0; The cjomposition' of claim 4 wherein said acid (a).issoyabean-oil acids': a 2; I

; Re f erencespite'd in the file of this patent The "Van-Nostrand=0hemists Dictionary, pp. 3 67-8, D; V-an Nostrand Q0; inc-NiY- 1953. (Copywin 5J

1. A NEW COMPOSITION OF MATTER COMPRISING THE ESTER OF (A) AN EPOXIDIZEDPOLYESTER OF TETRAHYDROPHALIC ACID THAN ONE EPOXY GROUP WHEREIN THENUCLEUS OF SAID THAN ONE EPOXY GROUP WHEREIN THE EPOXY OXYGEN ATOM ISLINKED TO ADJACENT CARBON ATOMS IN THE NUCLEUS OF SAID ACID WITH (B) THEDIESTER OF (A) AT LEAST NOE ETHYLENICALLY UNSATURATED ALIPHATICMONOCARBOXYLIC ACID HAVING AT LEAST ABOUT 10 CARBON ATOMS AND FREE OFALCOHOLIC HYDROXYL GROUPS WITH (B) A PENTANIOC ACID CONSISTINGESSENTIALLY OF 4,4 BIS4-HYDROXYARYL) PENTANIOC ACID WHEREIN THEHYDROXYARYL RADICAL IS A HYDROXYPHENYL RADICAL AND IS FREE FROMSUBSTITUENTS OTHER THAN ALKYL GROUPS OF FROM 1-5 CARBON ATOMS, THE ESTERLINKAGES OF SAID ESTER OF (A) WITH (B) BEING DEVELOPED AT LEASTPARTIALLY BY THE ADDITION OF THE CARBOXYL GROUP OF DIESTER (B) WITH THEEPOXY GROUPS OF THE POLYEPOXY POLYESTER (A).